Base-induced rearrangement of 1-(trimethylsilyl)allylic alcohols. Stereo- and regioselective synthesis of silyl enol ethers through lithium homoenolates
Stereoselective Synthesis of Tetrasubstituted Olefins through a Halogen-Induced 1,2-Silyl Migration
作者:Nicholas T. Barczak、Douglas A. Rooke、Zachary A. Menard、Eric M. Ferreira
DOI:10.1002/anie.201303007
日期:2013.7.15
Migrating through Si valley: The highly stereoselective formation of α‐silyl‐β‐ haloenones by way of silicon group migration is described. Electrophilic activation of the alkyne by N‐halosuccinimides induced an anti‐selectivemigration to give highly substituted enones (see scheme). These enone products can be readily converted to the all‐carbon tetrasubstituted alkenes while maintaining their geometry
copper-catalyzed highly enantioselective umpolung allylic acylation reaction with acylsilanes as acyl anion equivalents. Triplet-quenching experiments and DFT calculations supported our reaction design, which is based on copper-to-acyl metal-to-ligand charge transfer (MLCT) photoexcitation that generates a charge-separated triplet state as a highly reactive intermediate. According to the calculations
Currently, catalytically transferable carbenes are limited to electron-deficient and neutral derivatives, and electron-rich carbenes bearing an alkoxy group (i.e., Fischer-type carbenes) cannot be used in catalyticcyclopropanation because of the lack of appropriate carbene precursors. We report herein that acylsilanes can serve as a source of electron-rich carbenes under palladium catalysis, enabling
Carbeneinsertionreactions with B-H bonds are a challenging but promising method for synthesis of organoboranes. Herein, we report visible-light-induced B-H insertions of HBpin with acylsilane. This metal-free and operationally simple reaction pro-ceeds in an atom-economical way with broad substrate scope under mild reaction conditions, affording a variety of important α-alkoxyorganoboronate esters
Synthesis of aryl and alkyl acylsilanes using trimethyl(tributylstannyl)silane
作者:Feng Geng、Robert E Maleczka
DOI:10.1016/s0040-4039(99)00477-3
日期:1999.4
Palladium catalyzed coupling of acid chlorides and trimethyl(tributylstannyl)silane proves to be a convenient method for the preparation of both aromatic and aliphatic acylsilanes.